The present invention relates to an apparatus for disassembling bearing caps and assembling metals, which can parallelly perform disassembly of bearing caps which are tentatively or temporarily assembled to a cylinder block and assembly of metals to the disassembled bearing caps and the cylinder block.
In an engine assembly line, journal bearing portions are machined while bearing caps are tentatively assembled to a cylinder block. The bearing caps are then disassembled (removed) from the cylinder block. Upper metals are assembled to the cylinder block from which the bearing caps are removed. Lower metals are assembled to the corresponding bearing caps. A crankshaft and a thrust metal are assembled to the cylinder block in turn. The bearing caps are then assembled to the cylinder block, thus completing an engine.
Each bearing cap is fitted under pressure in the cylinder block and is fastened by a bolt. For this reason, it is cumbersome to disassemble the bearing caps from the cylinder block, and it is very difficult to automate the overall disassembling operations.
An apparatus which can automatically perform the disassembling operations of the bearing caps after removal of bolts is described in, e.g., Japanese Utility Model Publication No. 52-24311. The apparatus described in this prior art utility model comprises a pair of upper and lower sliders provided to a machine frame, a plurality of swing members which are attached to one slider and can be engaged with bearing caps from the above, and a plurality of support members which are attached to the other slider and have wedge-shaped pawl portions. One slider is moved while the swing members are engaged with the bearing caps from the above, so that the bearing caps are inclined through the swing members to form gaps between the bearing caps and a cylinder block. The other slider is moved to insert the pawl portions of the support members into the gaps. Thereafter, the bearing caps are moved toward the support members through the one slider and the swing members to be transferred onto the pawl portions, thus removing the bearing caps.
After the bearing caps are disassembled, upper metals must be assembled to journal bearing portions of the cylinder block, and lower metals must be assembled to the bearing caps which are disassembled and held at a separate location. It is relatively difficult to automatically handle and assemble these metals, and these operations have not been so automated until very recently. In recent years, however, a metal assembling apparatus described in, e.g., Japanese Patent Laid-Open (Kokai) No. 62-157741 is known. This prior art patent describes a mechanism for positioning a pair of upper and lower metals while switching them into a downwardly projecting posture and an upwardly projecting posture, a mechanism for causing a swingable suction head to draw each metal by suction and assembling it to a large end portion of a connecting rod and the cylinder block, and the like.
However, the apparatus disclosed in Japanese Utility Model Publication No. 52-24311 is not arranged integrally with a bolt disassembling means such as a nut runner. For this reason, in this prior art, before removal of the bearing caps by this apparatus, bolt disassembling operations must be performed in advance by the bolt disassembling means. As a result, the number of steps is increased, and a cycle time is prolonged. Furthermore, in the conventional apparatus, since the bearing cap disassembling apparatus and the metal handling apparatus are arranged not integrally with each other but independently, the entire system cannot be integrated, and the number of steps is unnecessarily increased, resulting in a long cycle time.